Reza Najafi; Taher Barzegar; Farhang Razavi; Zahra Ghahremani
Abstract
Introduction: Eggplant (Solanum melongena L.) is an important non-climacteric fruit grown in tropical and subtropical regions. The total production in Iran and world for eggplants in 2018 were estimated 54077210 and 666838 tons, respectively, and Iran ranked fifth in the production of this product. The ...
Read More
Introduction: Eggplant (Solanum melongena L.) is an important non-climacteric fruit grown in tropical and subtropical regions. The total production in Iran and world for eggplants in 2018 were estimated 54077210 and 666838 tons, respectively, and Iran ranked fifth in the production of this product. The health-promoting attributes of eggplant are derived from the phytochemicals with good source of antioxidants (anthocyanin and phenolic acids), dietary fiber and vitamins. Fruit deterioration during long term storage is associated with appearance quality reduction, calyx discoloration, softening and pulp browning caused by the oxidation of phenolic compounds. Hydrogen Sulfide (H2S) is a flammable and colorless gas, that similar to carbon monoxide and nitric oxide, is known as third leading signaling molecule. It has been reported that H2S play an imperative role in the postharvest physiology and chilling injury of various fruits and vegetables. In recent years, exogenous phenylalanine (PA) application has been employed as a beneficial procedure for enhancing quality in fruits and vegetables by promoting higher phenols and flavonoids accumulation arising from higher PAL enzyme activity and proline accumulation exhibiting higher ROS scavenging capacity. Thus, the aim of this study was to investigate the postharvest application of H2S and PA on quality and postharvest storage of eggplant fruit during storage at 7 °C for 21 days. Material and Methods: Eggplant fruits (Solanum melongena cv. Hadrian) were harvested at commercially maturity stage in Jun 2019 from a greenhouse in Hashtgerd city, Iran. Fruit selected for uniform size, shape, and color, and immediately transported to the laboratory. They were divided into seven parts for the following treatments: control (0), hydrogen Sulfide (H2S) at 0.1, 0.2 or 0.3 mM and phenylalanine (PA) at 2.5, 5 or 7.5 mM. Each treatment was done in three replicates, consists of 24 fruits from each replicate, and then randomly divided into four groups include six fruits. One group was analyzed 24 hrs. after harvesting and another groups stored at 7 ± 1 °C and 85% RH for 21 days. At 7-day intervals, one group was taken at random and transferred for one day at 20 °C (shelf-life), and subjected to physicochemical analysis. For H2S fumigation, fruit was placed at the bottom of a sealed 15 L container with different aqueous sodium hydrosulfide (NaHS) solution concentrations for 10 min, and for PA treatments, the fruits were immersed in 10 L of fresh phenylalanine solution for 10 min and in distilled water as a control. The fruits were allowed to completely dry at room temperature before storage. Results and Discussion: The results showed that fruits treated by PA and H2S exhibited higher fruit firmness, chlorophyll, anthocyanin, total soluble solids (TSS), vitamin C, pH and titratable acidity (TA) accompanied by lower weight loss and chilling indices during storage at 7 ºC for 21 days. In control eggplant fruits, fruit firmness (24.2%), chlorophyll (45.8%), vitamin C (34.1 %), anthocyanin content (66.2 %) and TA (44.8) decreased, and weight loss (7.5 %), TSS (8.2%) and chilling indices (4.5 %) increased during 21 storage time. The maximum fruit firmness (1.37 and 1.34 kg cm-2), anthocyanin content (5.02 and 4.2 mg L-1) and TA (18.67 and 1.37 %), and the lowest weight loss (3.67 and 3.7 %) and chilling index (1.6 and 1.3 %) was found in fruits treated with H2S at 3 mM and PA at 7.5 mM during storage at 7 °C for 21 days, respectively. It has been reported that texture correlates with firmness and higher firmness is a characteristic indicator of good texture during postharvest storage of fresh products. Soluble solid contents, titratable acidity (TA) and sugars have been known as important attributes contributing in overall sensory quality of fruits and vegetables. Development of the chilling injury disorder significantly reduces quality of fruits and vegetables due to diminished consumer’s acceptance. So, start of chilling injury symptoms eventually becomes economically critical postharvest constraint that defines the storage life potential of the products. Decline chilling injury in responses to H2S and PA treatments may resulted from higher ROS scavenging enzymes SOD, CAT, APX and POD activity and proline, phenols and flavonoids accumulation giving rise to conferring chilling tolerance. Conclusion: According to results, PA at 7.5 mM and H2S at 3 mM had the highest positive effect on maintain firmness and fruit quality and reducing weight loss and chilling, therefor postharvest treatment of PA and H2S can be proposed to improve fruit quality and postharvest life during storage period.
Fateme Shabbepour Bandari; Somayeh Rastegar; Mostafa Ghasemi
Abstract
Introduction: Ziziphus mauritiana is a drought-tolerant fruit tree that originated in Central Asia. Ziziphus mauritiana v. khormaee is one of the cultivars of Hindi Ber which was favored by many people in the world and Iran. Maintenance of fruit quality is critical while employing any new technology ...
Read More
Introduction: Ziziphus mauritiana is a drought-tolerant fruit tree that originated in Central Asia. Ziziphus mauritiana v. khormaee is one of the cultivars of Hindi Ber which was favored by many people in the world and Iran. Maintenance of fruit quality is critical while employing any new technology for increasing production. Fruit quality such as color, firmness, size, antioxidant and pulp to seed ratio had important role in marketability of fruits that can be affected by some chemicals. The quality of fruit can be influenced by growth conditions, developmental stage at harvest and postharvest factors. Calcium treatment, either by prearrest foliar sprays or by postharvest dips, represents a safe and potentially effective method for increasing the quality of some fruits. Prearrest treatments are more effective when calcium is applied directly to the fruit surface, since calcium moves in the transpiration stream and little or no subsequent translocation occurs from leaf to fruit. Calcium is an essential element which involved in cell division, elongation and fruit growth. Polyamines have the properties of growth promoters. Exogenous application of PAs has been reported to improve fruit retention and yield of fruits. Although a number of studies demonstrated the significance of PAs in reducing fruit drop and improving yield in various fruit crops, information on their effects on fruit quality is scant. Salicylic acid (SA) is an endogenous growth regulator of phenolic nature, which participates in the regulation of physiological processes in plants. Little information is available on the effects of foliar application of different Pas, salicylic acid and calcium on the quality of Ber fruit.
Materials and Methods: In this study, we evaluated the effect of foliar application of calcium chloride, putrescine and salicylic acid in various concentrations on fruit quality and quantity characters of Hindi ber(Ziziphusmauritiana. khormaee). Fruits selected from trees of the same age with branches of the same height and spraying with calcium chloride (0.5 and 1.5%), putrescine (1 and 2 mM), salicylic acid (1 and 2 mM) and distilled water (control) in two stages before commercial maturity. First stage, when fruit were 5-10 mm in size and second stage, when fruit color break. After the harvest fruit were transferred immediately to the laboratory and measured quantitative and qualitative parameters such as firmness, fruit length, fruit diameter, volume of fruit juice, pulp to seed ratio, soluble solids, titratable acidity, pH, ascorbic acid, chlorophyll a, b and carotenoids, color parameters and antioxidant activity. The length and diameter of the fruit were measured using a micrometer caliper. Total soluble solids (TSS) were determined using a digital refractometer. Firmness values of each individual fruit were measured at two points of the equatorial region by using a texture analyzer with a 5 mm Lurton 5005 probe. Fruits surface color was measured on individual fruit from each replicate at two opposite sides using a chromameter (CR 400, Minolta).For vitamin C (ascorbic acid) determination the titrimetric method with 2, 6-dichlorophenolindophenol reagent was applied. Antioxidant activity of fruit was tested by free radical DPPH scavenging.
Results and Discussion: The results showed that foliar application of calcium chloride, putrescine and salicylic acid favorably was effective on quantitative and qualitativecharacteristics Hindi Ber genotype.Kormaed. In treated fruits, total soluble solids (TSS), carotenoids and a* value were less and degree of firmness, fruit length, diameter, volume of fruit juice, pulp to seed ratio, titratable acidity, ascorbic acid (vitamin C), antioxidant activity, chlorophyll a and b, chroma index and hue angle were higher than control. Parameters of L* and b* in treated fruits had not significant different with control. Control fruits had the minimum carotenoid and the maximum chlorophyll. Fruit treated with putrescin(2mM) and control has the highest L* value. Different concentration of treatment that used hadn’t any significant difference with together in antioxidant characters. Maximum and the minimum firmness were found in salicylic acid (1mM) and control respectively. Among different treatments, CaCl2 1.5% showed highest volume of fruit juice of course had not significant difference with other treatments. The highest total soluble solids observed in control and highest vitamin C value showed in putrescin treatments
Conclusions: Generally, our result showed treatments that study in this study were effective on quality of Ber fruit. Calcium chloride (0.5 %), putrescine (2 mM), salicylic acid (2 mM) had the best effect on fruit quality. Therefor this chemical can be used to improve Ber fruit quality for consumer and marketing.
Materials and Methods: In this study, we evaluated the effect of foliar application of calcium chloride, putrescine and salicylic acid in various concentrations on fruit quality and quantity charachters of Hindi ber (Ziziphus mauritiana genotype.khormaee). Fruits selected from trees of the same age with branches of the same height and spraying with calcium chloride (0/5 and 1.5%), putrescine (1 and 2 mM), salicylic acid (1 and 2 mM) and distilled water (control) in two stages before commercial maturity. First stage, when fruit were 5-10 mm in size and second stage, when fruit color break. After the harvest fruit were transferred immediately to the laboratory and measured quantitative and qualitative parameters such as firmness, fruit length, fruit diameter, volume of fruit juice, pulp to seed ratio, soluble solids, titratable acidity, pH, ascorbic acid, chlorophyll a, b and carotenoids, color parameters and antioxidant activity. The length and diameter of the fruit were measured using a micrometer caliper. Total soluble solids (TSS) were determined using a digital refractometer. Firmness values of each individual fruit were measured at two points of the equatorial region by using a texture analyzer with a 5 mm Lurton 5005 probe. Fruits surface color was measured on individual fruit from each replicate at two opposite sides using a chromameter (CR 400, Minolta). For vitamin C (ascorbic acid) determination the titrimetric method with 2, 6-dichlorophenolindophenol reagent was applied. Free radical scavenging activity (antioxidant activity) of fruit was tested by DPPH.
Results and Discussion: The results showed that foliar application of calcium chloride, putrescine and salicylic acid favorably was effective on quantitative and qualitative characteristics Hindi ber genotype. Kormaed. In Treated Fruits, Total Soluble Solids (TSS), carotenoids and a* value were less and degree of firmness, fruit length, diameter, volume of fruit juice, pulp to seed ratio, titratable acidity, Ascorbic acid (vitamin C), antioxidant activity, chlorophyll a and b, chroma index and hue angle were higher than control. Parameters of L* and b* in treated fruits had not significant different with control. Control fruits had the minimum carotenoid and the maximum chlorophyll rather than other treatments. Fruit treated with Putrescin (2mM) and control has the highest L* value. Different concentration of treatment that used hadn’t any significant difference with together in antioxidant characters. Maximum and the minimum firmness were found in Salicylic acid (1Mm) and control respectively. Among different treatments, Cacl2 1.5% showed highest volume of fruit juice of course had not significant difference with other treatments. Control showed the highest Total Soluble Solids and significant differences with other fruits. Putrescin in both concentration had highest vitamin C content that had significant difference with control fruits.
Conclusions: Generally, our result showed treatment that study in this study were effect on quality of Ber fruit. Calcium chloride (0/5 %), putrescine (2 mM), salicylic acid (2 mM) had the best effect on fruit quality. Therefor this chemical can be used for improve Ber fruit quality for consumer and marketing.